Mycobacterium fortuitum mastoiditis.

Improved techniques of bacteriologic identification have led to increasing recognition of the clinical significance of the atypical or anomymous mycobacteria. Mycobacterium fortuitum, included in group IV of Runyon's classification because of its characteristic rapid growth, is widespread in nature as a saprophyte. Its facultative pathogenicity has received increasing attention in the literature recently with reports of a number of isolated infections, epidemics, and deaths. We report a case of mastoiditis due to M fortuitum and discuss the pathogenesis and treatment. This is the first known report of the organism causing otolaryngologic disease.